Bulk Mailer helps speed the delivery of an email message to many recipients using Sendmail. It's best used in parallel with a mailing list manager such as Majordomo. For input, it takes a file of recipient addresses (one address per line) and a message (with headers already attached) to be sent to the recipients. It sorts the recipient list by reversed domain (so similar ones sort together), splits up the recipients into several groups containing no more than N domains each, creates an SMTP envelope for each group of recipients, and feeds each envelope to sendmail.

Citadel is an advanced messaging and collaboration system for groupware and BBS applications. Users can connect to Citadel using any telnet, WWW, or client software. Among the features supported are public and private message bases (rooms), electronic mail, real-time chat, paging, shared calendaring, address books, mailing lists, and more. Unlike other collaboration servers, Citadel provides its own data stores and is therefore extremely easy to install; you don't have to "bring your own" email and database because they're built in. The server is multithreaded and scalable. In addition, SMTP, IMAP, and POP3 servers are built-in for easy connection to Internet mail. Citadel is both robust and mature; it has been in production since 1987.

cvsmail is a set of utilities to manage the delivery of CVS commit logs via email. It contains an email answering robot to manage the subscriptions and a delivering machinery. The subscription is done via modules for each CVS base handled by cvsmail.

eSquire is a majordomo replacement that provides a web frontend to most list manager functions. Subscribe / Unsubscribe functions use the majordomo style so users don't necessarily notice that it's not majordomo.

ezmlm lets users set up their own mailing lists within qmail's address hierarchy. A user, Joe, types ``ezmlm-make ~/SOS ~/.qmail-sos joe-sos isp.net'' and instantly has a functioning mailing list, joe-sos@isp.net, with all relevant information stored in a new ~/SOS directory.

ezmlm-web is a Web interface for the
administration of ezmlm-idx mailing lists. It has
user level access control, and allows you to
create, modify, and update any mailing list's
configuration as well as control the subscriber
base. ezmlm-web provides full support for all the
features of ezmlm-idx. The interface is template
based and can easily be customized or replaced. It
is translated into seven different languages.
Support for encrypted mailing lists (gpg-ezmlm) is
included.

The Java Apache Mail Enterprise Server (Apache James) is a 100% pure Java server, designed to be a complete and portable enterprise mail engine solution based on currently available open protocols (SMTP, POP3, NNTP). It requires Java 2 (minimum requirement is the JRE 1.4).

JergoBlatz! is a mailing list server with special functionality for play-by-email games, especially turn based games. Users can set options and send email to each other in character. It also includes a TK based GUI for setting up the configuration files.